Clutch



D. FIRTH ETAL CLUTCH Jan. 16, 1945.

Filed Sept. 2, 1942 2 Sheets-'Sheet 1 j@ "j j@ "Jan, 16, 1945.

D. FIRTH ET AL CLUTCHv Filed sept.y 2, 1942 2 Sheets-Sheet 2 Patented Jan-.'16, 1945 CLUTCH Davia Fil-ur and Manon L rue, south Bend, rnd.,

asslgnors to Dodge Manufacturing Corpora'- tion, Mishawaka, Ind.,

a corporation of Indiana Application September 2, 1942, Serial No. 457,026 8 Claims. v(Cl. 19293).

eiect in the clutch applying operation and to.

assure -prompt release action of the ,balls when the clutch operating means is shifted to release position. Another object is to provide a practicable and efllcient clutch of simple and compact construction and one which can be economically manufactured. These and subsidiary objects are accomplished by means exemplified in the accompanying drawings, wherein:

Fig. 1 is a central longitudinal sectional view of a clutch of one practicable construction embodying the invention.

Fig. 2 is a crosssection thereof taken on the line 2-2 of Fig. 1, looking in the direction of the arrows.

Fig. 3 is an end elevation looking toward the right hand end of Fig. 1.

Figs. 4 and 5 are enlarged detail views ofa fragmentary portion of the structure, Fig. 4 showing the relative positions of the parts thereof in the release condition of the clutch and Fig. 5 showingV the relative positions of said parts-in the applied or clutching condition.

Fig. 6 is a view similar to Fig. 4 showing a contemplated mod'ication.

Fig'. 7 is a central longitudinal sectional view of a duplex clutch embodying the invention, with certain additional features of advantage insuch duplex clutch.

Referring to Figs. 1 to14 ofthe drawings, theillustrative clutchv therein shown comprises a clutch hub l carrying `in driving connection therewith a pair of annular-clutch plates 2 and l cooperable to clamp'or squeeze' an interposed friction disc 4. The clutch hub iis to be flxed by and in driving connection with-.a rotatable member (not shown) to. be' clutch``eonnected to the shaft. One practicable -way\'of securing the.I

friction :disc to 'such rotatable 'carrying member is vby formins'the frictionl disc with peripheral teeth 6 to be :slidably interfltted'with internal teeth of a bell-shaped extension of such rotatable carrying member. Instead of the single friction disc 4 there may be a multiple of such discs arranged in alternation with plates carried by and in driving connection with the hub, as in Fig. 7.

In the clutching operation, the axially movable clutch plate 2 is forced towardthe clutch plate 3, and the thrust imparted to the latter is taken by the clutch hub which in this linstance has an end pliclty and metal washers I4 and il. Preferably,

lspo'ndingly shaped bores to on a shaft in driving connection therewith by ange I constituting a thrust shoulder. against which the clutch plate 3 abuts. The clutch plate 3 could be integral with the hub, but for slmeccnomical advantage in manufacture the construction shown is provided, according to which the clutch plate 3 is made as a separate element identical to the clutch plate 2 and the hub has said flange 1 to take the thrust imparted to the -clutch plate-2,v both clutch plates being slipped over and sildably fitted on the shaft which is cut away at opposite sides to form broad fiat surfaces 8, the two 'clutch plates having correflt the hub, whereby the hub and clutch plates are in. driving connection through engagement of the broad flat hub faces 8 with the corresponding bore portions of the clutch plates. The hub has a screw-threaded portion engaged by the correspondingly interiorly screw-threaded portion 9 of a tubular thrust member I0 functioning as an adjusting nut. Said member I 0 is shown as having a flange l I at the end thereof remote from the hub flange 1. A set screw I2` screwed through said ange against the hub secures saidmember III in fixed relation to the hub. Between the member i0 and clutch plates and abutting against the axially movable clutch plate 2 is an annular axiaily^movable thrusttransmitting member Il. Said member I3 could be integral with the clutch plate .2 but for simpliclty and economical advantage ismade as a separate. element, itsI function being that ofv an axially movable spacer for transmitting thrust to the clutch plates. The adjacent annular faces ofthe thrust members Il and i3 are axially separated and radially outwardly diverging, at least one of said end faces being conical. Seated against the respective said end faces arehard as ln the illustrative construction, the thrust member I0 has-a conical end face towhich is applied a. conical washer Il, whereas the thrust member I3 -has-t a dat endfface to which is applied a fiat il. Thus said adjacent' end faces or the thrust members and` the washers seated thereagainst diverge at an acute angle. A plurality of steel balls I6 arranged in an annular series bear against the confronting and outwardly diverging faces of said hardened metal washers, these balls being of such diameter that in the release condition of the clutch they project radially` outward beyond the peripheries of the thrust members I and I3. There may be a full complement of' such balls, in no greater num- -ber than to allow them to'be forced radially inwardly to the position shown in Figs. 1 and2; or there may be less than a full complement, the balls being suitably spaced by suitable spacing means. Thus there Imay be as few as three balls spaced approximately equal angular distances apart. The radial positioning of the balls is controlled by a revoluble and axially shiftable cam sleeve II mounted on the member I0 and operable by suitable means such for example as a clutch throw lever (not shown) having a yoke arm engaging the diametrically opposite. trunnions I8 of a collar I9 swiveled on the cam sleeve;

said collar, which has an internal annular channel engaging an annular rib on the cam sleeve,

being constructed in two half partsA bolted together as shown in Fig. 2.

In the release condition of the clutch, the cam .sleeve I'l abuts against the flange II of the'thrust member I0. In this position, the balls I6 contact with the interior cylindrical surface of the fore end of the cam sleeve, as shown in Fig. 4. As the cam sleeve is moved to the right from said release position to the clutch applying position shown in Figs. 1 and 5, the conical vinterior surface 20 of thecam sleeve engages the balls, forcing them radially inwardly so -that they act wedgingly to forcibly spread the thrust members Il! and I3 by axial displacement of the member I3 and clutch plate 2 which it abuts, thus forcing the frictional clutching elements into coaction or pressing them together. The interior surface of the cam sleeve at 2| is very slightly tapered reversely to the taper of the conical surface 20, so

that when the cam sleeve is forced full vway to the right the balls are engaged by said very slightly reversely tapered surface 2|, whereby the clutch is self-locking in applied or clutching condition. As the thrust of the bearing balls against the members I0 and I3 is transmitted through the hardened metal washers I4 and I5, said thrust members I0 and I3 are relieved from wear of the balls and may therefore be made of ordinary steel or soft cast iron or even cheap moldable material, whichisof important advantage for economy of construction.

.As the cam sleeve I1 is'shifted to the left from the clutching position shown in Figs. 1 and 5 to the releasel position shown in Fig. 4, the balls I6 Vare allowed to move radially outwardly by centrifugal force. Ordinarily, and especially if the shaft is rotating at fast speed, the centrifugal force would move the balls outwardly. However, if the balls bore directly against the adjacent end faces of the thrust mmbers Ill and I3 or against washers seated squar ly and unyieldingly thereagainst, which end faces and washers diverge at an acute angle, then in the clutch applying operation the ballsnilght become s o tightly wedged or jammed as to retard or interfere with the prompt outward movement of the balls as the cam sleeve is moved to release position. One of the objects of ythe invention is to avoid .such an objection, which is accomplished by means incidentally giv- 'ing a desirable'cushioning effect in the clutch applying operation. The means for such purpose 1 embodied in the illustrative construction .is S

follows: 'I'he conical washer I4 is a resilient element, being a continuous or unsplit conical washer of spring metal.. 'I'his washer I4 and the end face of the member against which it is seated are correspondingly conical in the sense that they slant in the same general direction, but the slant of the conical washer relative to a plane at right angles to the clutch axis is somewhat greater than the slant of said conical end face of the member I0, so that in the release condition of the clutch the conical washer I4, While bearing at its outer or peripheral portion against said conical end face has its inner or central portion separated from such end face, as is apparent from Fig. 4. In the clutch applying operation, said` conical washer is forcibly distorted or sprung out of shape by the forcing of the balls radially inwardly thereagainst, giving a desirable cushioning effect. As the cam sleeve is moved to release position, said conical washer reacts re- .siliently to assist in forcing the balls radially outl the' member'` I0, and a conical spring metal washer I5X is seated against the fiat end face of the member I3, with the depressed face of said washer I5X toward said flat end face so that in the clutch applying operation the washer IEX wouldv be sprung, giving cushioning effect, and

- in the releasing operation it would react resiliently to assist in forcing the balls radially outward.

The duplex clutch shown in Fig. 7 comprises in effect two reversely arranged clutches of the y same type as and generally similar in construction to thatalready described; each of said clutches comprising av hub Ia carrying in driving connection therewith a pair of clutch plates 2 and 3* cooperable to clamp or squeeze interposed friction disc means (shown in this instance as a multiple of frictiondiscs 4El arranged in alternation with other plates carried by and in driving connection with the hub), and each having an adjusting nut I0 and an axially displaceable thrust transmitting member I3a and an annular series of balls I6al engaging the confronting faces of hard metal washers seated against the'axially lseparated and outwardly diverging adjacent end faces of the members I and I3e.. Thetwo clutches are mounted on a common shaft 22 in driving connection therewith by a key 23 and secured against relative displacement by set screws 24 having dog point protuberances engagihg holes therefor in the key. The thrust 25 for access to said screws.

transmitting members I3a are provided with holes The two clutches are arranged'withl their adjusting nuts at adjacent ends, andthe two sets of balls are controlled .by the oppositely extendingrcam sleeve portions IIa of a revoluble and axially shiftable member 26 mounted on thev adjusting nuts and shiftable from one to the other, said member 26 having a shifter collar I9'L with diametrically opposite trunnions for engagement by the yoke arm of a clutch throw lever. The construction and arrangement-is suchthat when the member 26 is midway between the two sets of frictional clutching elements both sets .of lballs IGlare in yboth' clutches are their outward positions and released. Upon shifting the member 26 from such neutral position to either extreme position, one set of balls is forcedradially inwardly'to apply the corresponding clutch. The adjusting 'forcing frictional nuts Hl* are secured in xed relation to the clutch by lock4 screws 21 bearing-against small soft metal blocks 28 in engagement with the screw threads of the clutch hubs. Said'logk screws 21 have square sockets in their` outer ends lfor engagement of suitable wrenches.l The sleeve portions I1 of. the member 26 have holes 29 'of smaller diameter than the balls and so arranged that in either extreme position ofthe member 26 it can be'revolved to bring one of theholes 29 in registration with the corresponding lock screw 21. Fig. '1 shows the member 26,1n its extreme left handposition, applying the left hand clutch, the right hand clutch being released. The right hand hole 29 is shown in registration with the right hand lock screw 21, so that a suitable tool or; wrench can be inserted through said hole and engaged within said lock A be utilized as a lever for revolving the member 26 together with the-adjusting nut having the lock screw engaged by such tool. In this man ner the adjusting nut can be adjusted, after which the lock screw '21. in such nut can be' tightened by turning such tool. Whenthe member 26 is shifted to its extreme right hand position,

hand clutch and releasing the the left hand hole 29 can be with the lock screw 21 applying the right left hand clutch, brought into registration of the left hand clutch, so that with the use oi' such a tool and 4in the manner above described the left hand adjusting nut canbe adjusted and then fixed in relationship to its hub by tightening the said left hand lock screw.

We claim:

l. A friction clutch having, in combination, a 2

pair of coaxial annular thrust transmitting members adapted to be forcibly spread axially for forcing frictional clutching elements into coaction, the adjacent annular end faces'of said members being axially separated and diverging Vradially outwardly, a pair of hard metal washers respectively seatedagainst the respective said end faces. one of said washers and the end face to which it is applied being correspondingly conical, said conical washer being of Vspring metal and having apgreater slant than-saidl conical end face clutching elements into coaction, one of said means comprising a conical spring metal -washer andv a member having an annular end face against which said washer E seated, said washer being between said member and the other of said means and having its depressed side `adjacentdao said member, the confronting faces of said washer and other of said means diverging radially outwardly, an annular series vof bearing balls bearing against said con- '.fronting faces, and means for forcing said balls screw. Such tool can relative to a plane at right angles to the clutch axis, an annular series of bearing balls bearing against the confronting faces of said washers,

and means for forcing said balls radially inwardly to forcibly ,spread said pair of members by wedging action of said balls against said washers. 2. A'friction clutch having, in combination, a pair of coaxial annular thrust transmitting members adapted-to be forcibly spread axially for forcing frictional clutching elements into coaction, the adjacent annular end faces of said members being axially separated and diverging radially outwardly, a pair of hard metal washers respectively seated against the respective said end faces, including a conical spring washer` having a depressed side adjacent to the end face of the memberv to which itis applied and 'slanting rela-I ,tween said nut radially inwardly to forcibly spread said pair of means by wedging action of' said balls therebetween, said conical washer slanting relative to said end face of the member to which it is applied so that 'in the release condltionof the clutch the central portion of such'washer is unseated or separated from such end face, whereby in the clutch applying operation said washer is sprung out of shape with consequent cushioning eiect and in the releasing operation reacts resiliently to assist in forcing'theballs radially outwardly.

4. A friction clutch having, in combination, annular thrust transmitting means adapted to be forcibly spread axially for forcing frictional clutching velements into coaction, one of said means comprising a conical spring metal washer and 'an annular member having a correspondingly conical end face against which said washer is seated, said washer being between said member and `the other of said means, the confronting faces of said washer and other of said means diverging radially outwardly, an annular series of bearing balls bearing against' said confronting faces, and means for forcing said balls radially inwardly to forcibly spread said pair of means by wedging action of said balls therebetween, said conical washer having a greater slant than said conical end face relative to a plane at right angles to the clutch axis so that in the release condition of the clutch the central portion of said washer is unseated or separated.l from such end face, whereby in the Ato assist in forcing said balls radially outwardly.

l5. A friction clutch having, in combination, a pair of annular clutch plates and interposed friction disc means to be squeezed thereby, a hub carrying said plates in therewith, one of said plates being axially mov. able andthe other held so as transmitted thereto by such axially movable plate, said hub having a screw-threaded portion and a reduced unthreaded portion, an annular adjusting nut screwed on said hub, a set screw screwed through said nut against the reduced unthreaded portion of the hub for securing the nut in fixed relation to the hub, an annular ax-l ially movable thrust transmitting member ybeand axially movable clutch plate,

` the latter being between said member and the tive thereto so that in. its unstressed condition thrust transmitting the confronting faces of c other clutch plate, and means including an annular series of balls forceable radially inwardly as wedging elements between said nut and member for forcing said axially movable clutch plate toward the other.

6. A friction clutch having, in combination, a pair of annular clutch plates and interposed therewith, one of said able and the other held transmitted thereto by such axially movabl driving connection to sustain thrust Plate, said hub having a screw-threaded portion and a reduced unthreaded portion, an annular adjusting nut screwed on said hub, said nut having a flange at the end thereof remote from said platea-a set screw screwed through said flange against the reduced lunthreaded portion of the hub for securing the nut in fixed relation to the hub, an annular axially movable thrust transmit- `ting membery between said nut and axially movableclutch plate, the latter being between said member and the other clutch plate, an annular series of balls forceable radially inwardly as wedging elements between said nut and member for forcing said axially movable clutch plate toward the other, and operating means controlling the radial positions of said balls comprising a sleeve slidable on said nut and having an interiorly tapered surface engageable with said balls, movement of said sleeve being limited in one direction by abutment of said sleeve against said axially movable plate and in the opposite direc- .tion by abutment of said sleeve against said flange o n said nut.

`'7. A frictionk clutch'having, in combination, a pair of annular clutch plates and interposed friction disc means to be squeezed thereby, a hub carrying said lplates, said hub having a screw-threaded portion'and being cut away to the hub, whereby they areheld in driving conform opposite flat surfaces and said plates having correspondingly shaped bores and tted'onlated.

nection therewith, an adjusting nut screwed on said hub, a hub nange against which one of said plates abuts,v the other of said plates being between said one and the adjusting nut and being axially movable, an annular axially movable thrust transmitting member -between said nut and axially movable clutch plate, and means including an -annular series ofaballsforceable radially inwardly. as `wedging elements between said nut and member for forcing said axially movable clutch plate toward the other.

8. A duplex clutch comprising on a common shaft two mechanisms according to claim 3 having hubs carrying their respective 4sets of frictional clutching elements and adjusting nuts screwed on adjacent ends of said hubs'between said sets, the means for forcing inwardly the respective sets of'balls of said mechanisms being oppositely tapered internal surfaces of a common revoluble and axially shiftable sleeve, there being locking means for said adjusting nuts, both nuts and sets of balls being enclosed by said sleeve in -both extreme positions thereof and said sleeve having apertures registrablewith and through which said nut locking means` can be manipu- DAVID FIRTH.' MARION FAST. 

